Sorry I'm late. I finally managed to get a working serial console by wiring the PL2303 through a logic level converter. The spec said it would support both voltages, but only the 5V pins are connected on the one I got.
If it wasn't for thagrol the pi would've been fried already. Special thanks to you for warning me.
NP. But that is well documented. Pi GPIO are 3.3v only and always have been.
Also I apologise for any confusion about the problem. All I'm trying to do is have the boot process entirely over serial. Just having the video output there doesn't bother me. Thing is, when I power up the computer I have to cross my fingers and hope for the best. Once I tuck the computer neatly behind furniture there's nothing going into it except for power, ethernet and uart.
OpenBSD on arm64 safely defaults to serial console since it can't rely on there being a framebuffer at all. Now all that's left is figuring out how to get any initial messages and bootstrap loader to appear on the serial console as well. Should anything go wrong I could force an unexpected reboot and perform recovery with the ramdisk kernel.
How far down that rabbit hole do you want to go?
Lite should already send the kernel boot messages to the UART assuming it's enabled. IIRC there's a setting somewhere to enable the firmware bootloader's debug output there too. Check the official documentation.
I think the desktop images do the same but I can't be certain as one of the first changes I make is to disable the splash screen (change splash to nosplash) and remove quiet from cmdline.txt
USB mass storage boot would be a nice bonus, if at all possible.
Unless you have a very early 4B that has never had its firmware updated booting from a USB mass storage device should just work. As long as it doesn't need more than 1.2A@5V and you're using a 3A@5V supply.
Statistics: Posted by thagrol — Sat Jan 11, 2025 12:58 am
